As violent mobs of young men continued to wreak havoc in Philadelphia for a second summer in a row, Mayor Michael Nutter has taken a hard line against the roving “flash mobs,” tightening weekend curfews, endorsing stiff “stop-and-frisk” polices, and blasting the mostly black teenagers involved in the violence with fiery words from the pulpit this weekend.

About 50 teenagers were arrested Friday for violating the newly enforced weekend curfew. It is aimed at cracking down on mobs of young people responsible for random attacks on people and property.

The mayor’s crackdown has placed him in the center of a simmering debate about how black community leaders should respond to violence within their own community. On one side are those who admire the mayor’s take-no-prisoners rhetorical style and use of police force, while others say this approach lets the mayor off the hook for failing to address the needs of young black Philadelphians.

In a combative speech on Sunday at Mount Carmel Baptist Church in Philadelphia, Mayor Nutter said that young black men have to stop acting like "sperm donors" and "human ATMs." He admonished parents for failing to supervise and expect good behavior from their children. And he directly implicated habits and styles of some young black men in the city.

"If you walk into somebody's office with your hair uncombed and a pick in the back, and your shoes untied and your pants half-down, tattoos up and down your arms and on your neck, and you wonder why somebody won't hire you?" Nutter told the congregation "They don't hire you 'cause you look like you're crazy. You have damaged your own race."

"I am a proud black man in this country," Nutter said in a subsequent interview with the Associated Press. "It was a message that needed to be said. It needed to be said at this time . . . People have had enough of this nonsense, black and white."

To some blacks, this argument – the so-called "politics of respectability" long debated by black intellectuals – as well as concrete action to address flash mobs are welcome.

"Mayor Nutter deserves credit for stepping up and being a leader," said Deneen Borelli, a fellow with the National Leadership Network of Black Conservatives, in a statement. "Nutter is doing what Al Sharpton, Jesse Jackson, President Obama and the Congressional Black Caucus have thus far failed to do by speaking out against the epidemic of violent 'flash mobs' and rampant, random crime and violence."

But some Philadelphians criticized Nutter for airing the community's problems only when they crept out of traditionally black neighborhoods, where crime and murder rates have soared for years. "What really bothered me was when Nutter fired the age-old salvo that has historically evoked head-hanging shame among black folks," writes Annette John-Hall, a black columnist for the Philadelphia Inquirer.

Moreover, Nutter's strong language enables white society in America to downplay poverty as the root cause of the black community's problems, says Columbia University political scientist Frederick Harris, author of the upcoming book, "The Price of the Ticket: The Rise and Fall of Black Politics in the Age of Obama.” "If this discourse was led by Ronald Reagan, for instance, people would call him on his racism, but now that you have a black face to these explanations it gives it legitimacy," he says.

Some point to Nutter's curfew and aggressive "stop-and-frisk" policy as evidence of a growing gap between poor and middle-class blacks that has been exacerbated by the poor economy. A federal lawsuit was filed by the American Civil Liberties Union in November, alleging that the searches, which Nutter began when he came into office, were violating the rights of blacks and Latinos who had done nothing wrong.

Indeed, some have questioned whether Nutter is really a mouthpiece for black Philadelphians. The mayor’s popularity has consistently fared better in white wards. Former Mayor John Street, Nutter’s predecessor, told a newspaper last year that Nutter was “not a black mayor ... just a mayor with dark skin.”

Calling out members of their own community hardly new among African-American leaders. At the turn of the 20th century, W.E.B. DuBois, the author of "The Philadelphia Negro," criticized poor blacks for everything from bad eating habits to unkempt houses.

In a 2004 speech commemorating the 50th anniversary of the Brown v. Board of Education decision, famous Philadelphian Bill Cosby called out young black "knuckleheads" who he contended were undermining civil rights era gains for the black community.

President Obama has also talked about the problem of single parenthood in the black community, and even once admonished young black men to pull up their saggy pants.

"If we are honest with ourselves, we'll admit that what too many fathers also are is missing – missing from too many lives and too many homes," Obama told a church in Chicago in his famous "Father's Day Speech" in 2008. "They have abandoned their responsibilities, acting like boys instead of men."

Black leaders are torn between the need to call for personal responsibility and the apparent willingness by many whites and some black leaders to assume that poverty and the dysfunction it brings can only be alleviated by the individual, not greater society.

"The black community needs to take a great deal of responsibility for these kids who are flash-mobbing," says Phillip Jackson, the founder of the Million Father March in Chicago. "You can't stop a flash mob when they're 15, 16, 17, when they're committed to lifestyles and to the acts at that point. But when they're 2, 3, 4 and 5, you can train them away from that behavior, and you can make them into almost anything you want them to be, but we [as a society] don't make that investment."